This invention relates to an improved piston shaft seal assembly and seal arrangement therein for end-of-car hydraulic cushioning devices.
End-of-car hydraulic cushioning devices which are used to control forces transmitted to a railcar during high velocity impacts are well known in the prior art. Typical examples of such prior art cushioning devices and their components are illustrated in U.S. Pat. Nos. 2,944,639; 2,944,681; 3,047,162; 3,152,699; 3,207,324; 3,233,747; 3,301,410; 3,451,561; 3,463,328; 3,495,719; 3,568,855; 3,589,527; 3,589,528; 3,598,249; 3,604,568; 3,647,088; 3,752,329; 3,791,534; and 3,854,596.
Prior art piston shaft seal assemblies and seal arrangements therein while satisfactory in service each comprise a large number of components making them expensive to manufacture and maintain parts therefore in inventory.